Choi Sung Ho's Singularity (최성호 특이점) is a Korean jazz and improvised-music group led by the guitarist Choi Sung Ho (최성호). Its first album came out on February 18, 2016, and by 2019 it had released four records on the Mirrorball label. One of them, When the Wind Blows (바람 불면), won the jazz album prize at the 14th Korean Music Awards in February 2017. EBS Space Gonggam, the Korean concert-television series, describes the group as a project in which the guitarist makes music with his friends, a container with no fixed shape. The Korean word teugijeom in the name means "singularity," and EBS glosses it with the physics sense: the point where gravity becomes infinite, the laws of physics stop applying and what happens next cannot be predicted.

Very little is published about Choi himself. No source found gives his birth year or birthplace, or says where he studied. What exists comes from EBS's two profiles of the group and a Bugs review. EBS wrote in 2017 that his mother had trained as a singer and that he spent part of his childhood abroad, so he grew up hearing rock, jazz, classical music, Korean pop, traditional Korean music and music from other parts of the world. EBS added in 2019 that as a boy he secretly copied Michael Jackson's dancing and sometimes imagined a life as a scientist shut in a laboratory, before music, and jazz in particular, took over, with a guitar already in the house. He calls himself a person who listens, plays and imagines. A Bugs reviewer in 2016 described him as someone who came to music from physics.

The lineup has changed shape from record to record. The first album, 어떤 시작 (literally "a certain beginning"), is a guitar trio without a bassist: Choi with the pianist Lee Seong-yeop (이성엽) and the drummer Dayeon Seok (석다연). From the second album on, the pianist is Han-earl Lee (이한얼), the bassist is Kim Do-young (김도영) and the drummer and percussionist is Seon-Yeol Baek (백선열). That quartet is on When the Wind Blows, on the 2017 EP and in EBS's 2017 concert. The 2019 album and the EBS concert of that year credit only Choi, Kim and Baek.

어떤 시작 (Mirrorball Jazz World MJW0191) was released on February 18, 2016, seven tracks and 43 minutes. Discogs credits Choi as producer and as composer of tracks two to seven, and lists the group itself as composer of the 2:39 opening piece. Bugs named it one of its albums of the month for March 2016. Its reviewer, Kim Gwang-hyeon (김광현), wrote that it brought real comfort at a time when jazz records contain less and less improvisation, singled out the percussive free guitar of the opener "사건의 지평선을 넘어" (roughly, "Beyond the Event Horizon"), and heard the influence of Bill Frisell and Min Yeong-seok (민영석) in the careful volume control and varied guitar techniques. Bugs's own description of the album speaks of playing that runs from traditional guitar technique to prepared guitar, between the familiar and the strange. Discogs lists the album as recorded at the James L. Dolan Music Recording Studio and mastered by Jonathan Wyner, with the mixing by Lee Byeong-seok (이병석).

When the Wind Blows followed on November 10, 2016 (MJW0226, six tracks, 49 minutes). The label's description says the pieces take their motifs from anecdotes, thoughts and feelings connected to the wind, and that the band keeps walking the line between mainstream and non-mainstream. It opens with "도시의 하루" ("A Day in the City," 10:11) and closes with "자유즉흥" ("Free Improvisation," 4:53). Discogs credits all of the music to Choi, with Lee on piano, Kim on bass and Baek on drums and percussion, and gives Lee Byeong-seok the recording, mixing and mastering.

On January 31, 2017, EBS Space Gonggam recorded the quartet for its series "Korean Jazz's New Faces 2017," the fourth of four concerts by artists who had released a first leader album in 2016, alongside the vocalist Pyo Jin-ho, the flautist Kim Eun-mi and the pianist Kang Ji-eun. The programme, which EBS broadcast on February 16, 2017 as episode 1304, included "도시의 하루," "흩날리는 생각들," "하늘 위로 내리는 눈," "소리가 차갑다" and "어떤 시작," plus free improvisations. In the EBS profile Choi says that his music mostly starts from very ordinary feelings in daily life, and that he wants concerts in which people can feel the value of ordinary days together.

At the 14th Korean Music Awards, held on February 28, 2017 at the Guro Arts Valley Arts Theater in Seoul, When the Wind Blows was nominated both for Best Jazz & Crossover Jazz Album and for Best Jazz & Crossover Performance. It won the album prize against five other nominees: 윤석철 트리오 (자유리듬), 이명건 트리오 (피고지고), 임인건 (Janus, The Reminiscence), 전재근 (Vignette) and Trio Closer (more Human). The performance prize went to Black String for Mask Dance, and Second Moon's Pansori Chunhyang-ga won the crossover album prize. The jury member Kim Hyeon-jun (김현준) wrote in the awards' citation that the record embodies the paradox that keeps jazz alive, honouring tradition while being able to take its values apart, that its composition, with a flavour only Korean music has, deserves as much notice as its emphasis on improvisation, and that over the coming years listeners would watch a new chapter of Korean jazz open through the group or through Choi himself. A few news reports called the prize a jazz and crossover song award. The awards' own 2017 results list it as the jazz album prize, the nominations that year included no song category in that genre, and English Wikipedia files it under Best Jazz & Crossover Album, Jazz.

Naver's OnStage series put the group on video as its episode 350, performing "어떤 시작" (Korean Wikipedia's list of OnStage performers dates it to August 2, 2017). On October 17, 2017 Mirrorball issued 다르다와 틀리다는 다르다 (Different Is Different from Wrong, 62 minutes, six tracks). Bugs lists it as an EP, though the label's own text calls it the third full album by the group that won the 2017 jazz album prize. The quartet is joined by the vocalist Nam Hyeon-ju (남현주) on its first four pieces, the longest of which runs more than 13 minutes ("도시비," "City Rain"). The label describes a record in which familiar, accessible material and abstract, experimental material sit side by side, and presents the title as an argument for treating difference as a source of variety instead of as something wrong. It closes with "근정전 앞마당에서" ("At Geunjeongjeon Front Yard," 11:49).

In 2018 Choi hosted a short podcast, 기타리스트 최성호의 음악중계, which ran to 16 episodes on Apple Podcasts and covered jazz and improvised music. Its twelfth episode, listed on April 6, 2018 and titled "특이점이 온다," has the pianist, bassist and drummer of the quartet as guests and discusses a performance the band gave on March 30, 2018 at 공상온도, a venue near Hongik University Station in Seoul.

The fourth album, 주기율표 / The Periodic Table, appeared on July 25, 2019 (seven tracks, 62 minutes). Bugs's credits give the guitar and voice to Choi, the bass to Kim Do-young and the drums to Baek Seon-yeol, with all compositions and words by Choi, production by Kim Se-min (김세민) and Choi, and recording, mixing and mastering at STUDIO877. The label says the record uses spoken words and writing to widen the listening experience, turning small everyday episodes into improvisation, and that its title piece takes its idea from Primo Levi's book The Periodic Table, in which chemical elements and episodes of a life are linked. EBS recorded the trio on September 26, 2019 on a double bill with the rock band Atom Music Heart and broadcast the show on October 18, 2019 as episode 1450, announcing music from the fourth album. EBS adds that each month the group collects stories from its audience and answers them with an improvisation.

The most recent release found is The Periodic Table in 2019. No later recording, concert listing or statement about the group's status turned up, so whether it is still performing is not known.

Choi has not been quoted naming his influences in anything found, so this section stays with what the records, the label copy and the critics say.

Discogs files both 2016 albums under jazz with the style tag Free Improvisation, and EBS describes music that sits on the border of mainstream and non-mainstream jazz: dreamy colours and quick intuition, genres that should not fit together sharing a piece, a familiar, song-like sensibility alongside a free-jazz vocabulary, passages that are rough or fierce and then fragile. The 2016 Bugs review hears careful dynamics and a wide guitar vocabulary that runs from conventional playing to prepared guitar, with echoes of Bill Frisell and Min Yeong-seok, and the 2017 EP's label text puts friendly, accessible material and abstract, experimental material in the same record. The 2019 album adds spoken words and text.

The group's working method is improvisation tied to ordinary life. Choi says his pieces come mostly from plain everyday feelings, the track titles of 2016 speak of wind, a cat's paw prints, snow and a day in the city, and by 2019 the band was turning audience stories into improvised pieces.

The listening Choi shared on his 2018 podcast gives a picture of his taste. His own picks and subjects included Ornette Coleman's album Body Meta, an interview with the guitarist Marc Ribot, an interview with the composer and saxophonist Henry Threadgill, and, in the episode about his own quartet, a free improvisation by the pianists Kris Davis and Angelica Sanchez, from which the band members each picked their favourite ten seconds.